Domestic heater



Dec. 28, 1937. D. J. MOSSHART DOMESTIC HEATER Filed Sept. 30, 1955 6 Sheets-Sheet 1 INVEN'TOR Dec. 28, 1937. D. J MOSS 2,103,789

DOMESTIC HEATER Filed Sept. 30, 1955- 6 Sheets-Sheet 3 Dec. 28, 1937.

D. J. MOSSHART DOMESTIC HEATER Y Filed Sept. 30, 1935 6 Shets-Shet 4 INVENTOR Dec. 28, 1937. D J MOSSHART Y I 2,103,789

DOMES TIC HEATER Filed Sept. 50, 1955 6 Sheets-Sheet 5 D. J. MOSSHART DOMESTIC HEATER Dec. 28, 1937.

s Sheets-Sheet 6 Filed Sept. 30, 1935 INVENTOR '1 Wm} Patented Dec. 28,

DOMESTIC HEATER,

Donald J'. Mosshart, Springfield, Pa., assignor of one-half toHarold'F. Hildreth, 'Mansfield, Ohio Application September so, 1935, Serial No. 42,787

S- PATENT OFFICE 13 Claims.

This invention relates to' fluid heat exchange apparatus, and more particularly to fluid heaters of the. domestictype, such, for example, as sectional cast iron boilers.

According to one form of my invention, I provide a fluid heater in which a furnace combustion chamber is enclosed by hollow metallic sections which not only promote effective transfer of heat to the enclosed fluid, but provide sucha combustion chamber and-flue construction. that lowcost fuelscan be employed to advantage.

It is an objectofthe invention to provide a heater of the type referred to above, in the operation-of which the furnace gases move in'such a path that the separation and removal of fly ashwithin the heater is facilitated and ash pick up by the furnace gases minimized.vv

A further object of the invention is to provide a furnace and fluid heater in which there isan increased amount of heatabsorption by convection in gas pass zones: beyond a radiant absorption zone. The latter is provided by the combustion chamber, and the convection absorption takes place mainly in a plurality of. gas

passesbeyond the combustion chamber andcommunicating therewith.

A more specific objectis the provision of a fluid heater of the domestic type, in whichthe furnace gases are exhausted .therefrom at acentral' position so related' to the gas passesthatthelatter. may be said to have a spiral, or cyclone ac-.

tionaround their pointof exit from the heater.,

Again, the invention comprehends a fly ash collection zone substantially tangentially related to the cyclone movement of. the furnace gases to the end that thecyclone movement. promotes ash deposition. and minimizes ash pick up.

Other objects of the invention will appear from the following description which has reference-to the attached drawings.

In the: drawings Fig: 1' is 'ayertical section through one-embodiment of the invention selected here for the purposesof illustration.

Fig. 2 is a transverse section taken on the section line 2--2of Fig. 1.

Fig. 3 is a horizontal section of the boiler shown in Fig. 1, taken on the line 3--3 of Fig. '1.

Fig; 4 is a'horizontal sectiont'aken on the line 50' of Fig. 1;

: of. Fig. 5.

it may be embodied in other types of heaters ofmodified construction, for example, certain features of! my invention may be embodied in bothhot water and hot air heaters of various types.

Referring to the boiler .shown in Fig. 1 of the drawings, the furnace having a combustion chamber til-may be. fired by a stoker I2 preferably constructed in accordance with the teachings of the inventions described in my co-pend-- ing application Ser. No. 17,162 filed on April 19, 1935 and having the title Combustion apparatus. This stoker is equipped with suitable means to provide a forced draft toincrease the rate of combustion of the fuel often resulting in the delivery of fly ash to the flues. Thecombustion chamber has a top outlet, and the furnace gases proceed under theforced draft through this outlet as indicated by the arrow 14. They then continue substantially horizontally as indicated bythe arrows l6 and [8 around and in between uprightwater circulating parts of the boiler 20- and thereby promote their separation from the gases.

The flue construction 26 is circular in cross section as indicated in Fig. 2 and it is embraced by a downwardly extending baffie 32 which-is indicated in dotted lines in Fig. 1. The configuration of this baffle is illustrated in Figs. 3 and 4 wherein the baffle is shown as extending from the upper side of the flue construction 26 to a positionebelow its center. In this case the bafiie is placed in position around the .flue 26 before the boiler sections 34, 36, 38, and 40 are secured together in their operative positions.

In conjunction with the rear wall 28 of the boiler the baflle 32- forms a downwardly tapering gas pass below which there is a fly ash receiving zone wherein the fiy ash may be collectedin a chamber 42, or discharged from that: chamber by a fluid nozzle 44 supplied with a fluid under pressure by a fluid pressure line 46 and discharging into a conduit 43. When such fluid operated ash discharge means is not used the fly ash may be collected in a removable re- 5 ceiver which may conveniently slide into the chamber 42.

The fly ash receiving chamber is advantageously located in a position somewhat tangential to the turn of the furnace gases around the lower end of the baflie 32 indicated by the arrow 50. Thus, there is an additional turn of the gases which promotes fly ash collection in the chamber 42. The arrangement of elements causing this gas travel also minimizes fly ash pickup adjacent the collection zone.

construction 26.

In connection with the above described movement of the furnace gases it will be noted that they may have several turns about the elements 20 and 22, to further promote ash deposition.

It will also be noted that the general flow of the gases is first around the exterior of the gas confining passages of the boiler and then into the interior location provided by the chamber 52. This arrangement results in a substantially spiral, or cyclonic gas flow which promotes complete combustion and minimizes the quantity of fly ash discharged by the furnace gases-into the atmosphere.

Fly ash deposits upon the surface forming the gas passes may be periodically removed by flushing them into the chamber. To this end, the lower wall 56 of the horizontal section of the first gas pass above the combustion chamber H3 slopes downwardly, as shown in Fig. 1, towards 4.0ithe flue construction 26. These sloping surfaces are provided by transverse parts of the boiler sections 35 and 38. The latter is indicated at 54 and it will be noted that the lower walls of this transverse portion form a part of the roof 45 of the combustion chamber In while the upper walls form the lower rearwardly sloping surface of the upper part of the first gas pass. This sloping wall is substantially continuous with the upper wall 56 of a transverse part of the section 38 and it will be understood that this sloping surface continues around the connecting portions 20 and 22. It terminates at a position rearwardly of the forward end of the flue construction 25, as indicated at 58. In this con- 55 nection it will be seen that the transverse connection portion of the section 38 also forms chambers 60 and 62, the forward wall 64 of which constitutes a part of the water cooled wall surface of the combustion chamber while the rear- 60 ward wall 66 forms a wall of the gas outlet chamber 52. 7

The fly ash deposits upon the forward surfaces of the first gas pass may be removed by fluid streams emerging from the pipe 68 which 65 is connected externally of the boiler with a source of fluid under pressure. When water is used for this purpose it discharges through openings 10 in the pipe 68 and causes the ash deposits to be sluiced into the rearward part of the first 70 gas pass and over the flue construction 26, and

into the ash receiving chamber 42. Ash deposits in the rearward part of the first gas pass and on the surfaces of the baffle 32 and the flue 26 may be removed by fluid streams emerging 7 through openings in the tube 12 which, like the tube 68, is connected to a source of fluid under pressure. Because of the fact that the gas passes are arranged as'shown, the fly ash deposits on the walls of the gas passes may be removed while the boiler is in operation, and without interrupting the continuous burning of fuel in the combustion chamber ID.

A relatively high degree of radiantly transmitted heat is absorbed by the water or other fluid in the boiler sections 34, 36, and 38 in a radiant heat absorption zone around the combustion chamber 10. To this end, and to prevent the burning out of furnace portions adjacent the stoker l2, the walls of the furnace chamber are all water cooled. The front wall 14 is indicated in Fig. 1 as a part of the boiler section 34 which is hollow as shown. This section not only includes the wall 14 but a parallel outer wall 16 permitting water to continuously move upwardly along the front wall of the furnace and to move in the direction of the arrow 18 through one of the openings 80 which connect the boiler sections at the top of the boiler. The rearward wall of the furnace is formed by the parts of the boiler section 38 which include the chambers 6i! and 62. Through these chambers water moves continuously upward to the top of the rear section of the boiler. The flow of water in this case is indicated by the'arrows S2, 84 and 86. This part of the circulation of the water is promoted by the inclination of the transverse connection portion of the boiler section 38 as it is indicated in Fig. 2 of the drawings. This View, in connection with Fig. 1 shows that the surface 56 provided by this connection portion not only slopes rearwardly of the boiler toward the ultimate gas discharge in the flue construction 26 but also slopes upwardly as shown toward the boiler wall 88.

In connection with the flow of gases in the first gas pass and the flow of water or other fluid as indicated by the arrows 82 and 84, it will be seen that there is a counterflow relation, the gases moving generally downward to a position below the lower end of the bafile 32, and the contained fluid flowing upwardly along the Walls of the gas pass and toward the boiler outlet 90 which may ing or other building.

The boiler sections also form water cooled side walls for the furnace, as clearly indicated in Figs. 3 and 4. In the former figure the positions of the upright fluid circulating parts of the sections 36 and 38 are well indicated. The portions here referred to are those indicated at 20 and 22. The rear wall of the boiler is water cooled by fluid circulation between the walls 28 and 92 of the rear boiler section 40.

In the operation of the stoker 12 a fuel bed is moved rearwardly of the furnace along its floor 93 and through an opening 94 through which ash may be discharged into an ash receiver 96, the continuous and advantageous burning of a low cost fuel being facilitated by the action of theat the lower parts of the boiler sections, and posi tioned as indicated in Fig. 2.

The upright fluid connectors 22 communicate with the side wall fluid passages of the boiler section'ih throu h the tra sverse connectors havin an upp r water well 56 andsa rear wa l 58.. The transv rse passa e formed thereby is indicated at I06 in Fig. 4.

In the embodiment, of the invention indicated inFig. 5 of the drawings, the combustion chamber I116, fired byv the stoker N18 is positioned at one. side of the boiler, and thegases rise upward- 1y and nake a turn indicated-by the arrow H0, inproceeding through the combustion chamber outlet H2. From this point they proceed aroundv the inclined. fluid; circulation passages H41: aszindicated by the arrow. H6. After the second-turn they-pass downwardly through apart of the first gas pass :8,- which is preferably spaced, from the wall; I10, of the combustion h m er. In pas in ownwardly throu h his s spassthe sas sare diyided Q- at they turn and pass around tubularconnections I22, forming. inclined iwater passages connecting thodownward water, flow in the passage I24 to thellpward water flow. a d pa sa e 26. which;v isformed; etween the wall I20, and other wall I2I formed in the boiler, sections.

The first gas pass I I8 is separated from. the s c d as. pass. I28 by an upr ht a le I30 whi h term hatesahov afly ash r c pta le 3! The gasespassaround. the lowerend of this-bafile I30: d t pw rd y thr u h-th econd p s I26. From the outlet, of; the. latter the gasesproc ed o t lls Itw l thusbe se n thatthe sas w. n. h s mb diment f he invention is similar to the gas flow in the Fig. lembodiment, at. leastt theextent that: e e. s. a general y pir r y lon c gas-"flow w h h lastpass and the ultimate gas outlet. enveloped, or embraced by the first gaspass which is generally U-shaped. Thus, effectively. complete combustion is promoted withoutincreasing'fly ash pickup. Also, relatively complete fly ash deposition nd c ll ct o it n. he re e v 3 s p omoted by the location of the receiver at the bottom of; the downward gas pass H8, and its are ran me t e y it is su ta t a ly t n ntial: 1y arran d wi h r r n e o e, ur f the gases at the bottom of the secondgas pass, as, ndi a d. y the. arrow l36- It will also be seen, in connection with the embodiment of the invention shown in Figs. 5, 6, and 7 that provision is made for the sluicing of fiyash deposits while the. furnace-isin'operation. The. means for accomplishing this; is similar to that shown in connection .with theFig-. lembodiment,'and it includes the water spray tubes I38 1 and I40 connectedwith ascurce of fluid. under pressure, and-sq positioned with reference to. the I inclined surfaces. provided byithe walls of the passages I22 and other surfaces in the gas passes,

that. all ofthe water I used forashremoval, and the deposited-ashes are sluiced intothe chamber I34. The upper tube l4flr-mayn-beyheld in position ,by an upward wall extension I44,- which also prevents the sluicing water or other. fluidfrom flowing into the combustion chamber I06.

In general, the boiler of the embodiment" indicated in Figs. 5, 6, and 'l'is a sectional boiler such as that indicated in the other embodiment. The extent of these sections is clearly indicated in Figs. G and 7', the sections being designated by the numerals I50, I52, I54, and I56. Thewalls ofthe combustion chamber of, this. embodiment arewater cooled by reason of'the hollow construction of .thesesections, and; the. furnace is, fi ed; by SPQKQI! '08:. imilar. to, they Stoker.

mechanism used in connection with the Fig; 1 embodiment.

As a result of the spiral movement of the gases, fly-ash and dust carried in suspension by the gases arethrown by centrifugal force to the outer walls of the gas passes, and the particles thus thrown against the rear wall of the down pass are moved directlytoward the ash receiving zone by gravity and the movement of the gases. For wardly of this zone, and toward the gas pass, the gases make a sharp turn so that gravity, loss of velocity, and centrifugal force further promote separation of the solid particles, and their-collection in the receiving zone. An important feature of this construction is that the ash particles sep; arated from the stream move to the outside walls of the gas passes and enter the ash receiving means without again entering the stream.

Referring again to its circulation and heat absorption features, the illustrative boiler in,- cludes connected boiler sections formingv a. water circulation system which presents zones of primary and-secondary heat absorption characteristics. In the primary zone, immediately adjacent the furnace walls, the water receives, its heat directly from the fire by radiation and convection. This is the more active part of the boiler and it includes. water uptake passages around the combustion chamber, with a steam libera=- tion space above. The boiler surfaces and' the water passages (including additional downcomer passages) are so arranged that water heated in: the more active part of the boiler can risedirectly to the steam liberating space; Water heated in the more active zone is replaced by cooler Water flowing from a less active boiler part (convection heated) directly to the lower portion of the more active zone.

The less active portion of the boiler receives heat from the cooler products of combustion, mainly by convection. It acts somewhat as. an economizer section, and the waterpassages connect this section to the more active boiler-sec- 'tion so that the combined effect of heating the water at different rates inthe twosections and directing the flow through the sections produces a positive unidirectional flow through each section. Priming and water hammer, and their deleterious effects are thereby prevented.

The illustrative boiler may be connected to theheating units of a domestic heating, system by means of such tubular conduits asthose indicated in Fig. 6 at I'6Il and I62. They. com-.. municate with the fluid circulating space of the boiler, and when the boiler is usedin a steam heating system they are in communication with the steam liberation space.

In further reference to the Fig, dboiler, it is to be noted that there is a receiver I'Skpositioned below the stoker and the ash exit opening I66. at the rear of the stoker. Above this opening, there is a transverse heating fluid chamber I68. formed preferably as an integral part of the furnace section I 54 which includes the water cooled wall I10. Mechanisms similar to that shown at 98 and Hill in Fig. 1 may be em.- ployed at a position adjacent the rear wall I12 of the chamber I68.

While I have shown my invention in but two forms, it will be obvious. to those skilled inthe. art that it is not solimited, but is susceptible of various changes and modificationswithout. departing fromthe spirit thereof, andIdesire; therefore. t at only such limitations, shall, be. pla ed hereupon as... are imposed: by: t p r art or as are specifically set forth in the appended claims.

What is claimed is:

1. In a domestic fluid heater, in combination, water cooled walls including side walls, a front wall and a back wall, a transverse wall extending from side to side and forming with the front and parts of the side walls a combustion chamber, a deflector wall extending forwardly and rearwardly from the top of said transverse wall, a top wall spaced from said deflector and defining with it a substantially horizontal gas pass, a flue extending through said rear wall below said deflector wall level and forward toward said transverse wall, a baiile depending from the rear edge of said deflector wall, being pierced by said flue and defining with the back wall a substantially vertical downward gas pass, gas from the last mentioned pass entering said flue after turning sharply beneath said baffle and a fly-ash receiving zone below the lower edge of said bailie and substantially tangential to the direction of gas flow at said turning.

2. In a domestic fluid heater, in combination, water cooled walls including side walls, a front wall and a back wall, a transverse wall extending from side to side and forming with the front and parts of the sidewalls a combustion chamber, a deflector wall extending forwardly and rearwardly from the top of said transverse wall, a top wall spaced from said deflector and definding with it a substantially horizontal gas pass, a flue extending through said rear wall below said deflector wall level and forward toward said transverse wall, a bafile depending from the rear edge of said deflector wall, being pierced by said flue and defining with the back wall a substantially vertical downward gas pass, gas from the last mentioned pass entering said flue after turning sharply beneath said bafiie and a fly-ash receiving zone below the lower edge of said bailie and substantially tangential to the direction of gas flow at said turning, said deflector wall being inclined downwardly toward said rear wall to retard the rate of gase move-- ment.

3: In a domestic fluid heater, in combination, water cooled walls including side walls, a front wall and a back wall, a transverse wall extending from side to side and forming with the front and parts of the side walls a combustion chamber, a deflector wall extending forwardly and rearwardly from the top of said transverse wall, a top wall spaced from said deflector and defining with it a substantially horizontal gas pass, staggered water tubes connecting said top and deflector wall water spaces and arranged in said horizontal gas pass, a flue extending through said rear wall below said deflector wall level and forward toward said transverse wall, a baiile depending frcm the rear edge of said deflector wall, being pierced by said flue and defining with the back wall a substantially vertical downward gas pass, gas from the last mentioned pass entering said flue after turning sharply beneath said bafiie and a fly-ash receiving zone below the lower edge of said bafile and substantially tangential to the direction of gas flow at said turning.

4. In a domestic fluid heater, in combination, water cooled walls forming a closed compartment, a wall extending transversely of said compartment for a part of the height thereof to divide it into a combustion chamber and space for passages with convection-heated surfaces, a deflector wall on top of said transverse wall extending over the chamber and-oppositely beyond said transverse wall, means in the vertical passage behind said transverse wall and below the deflector wall to split the gas stream and reduce its total crosssection and increase its velocity, a baffle for each section of the split stream and having a substantially horizontal lower edge, means to turn the gas streams sharply beneath said lower edge, said splitting means comprising a flue for merging and carrying oif said streams and a fly-ash receptacle beneath said bafiie edge.

5. In a domestic fluid heater, in combination, water cooled walls forming a closed compartment, a wall extending transversely of said compartment for a part-of the height thereof to divide it into a combustion chamber and space for passages with convection-heated surfaces, a deflector wall on top of said transverse wall extending over the chamber and oppositely beyond said transverse wall and inclined away from said combustion chamber, means in the vertical passage behind said transverse wall and below the deflector wall to split the gas stream and reduce its total cross-section and increase its velocity, a baflle for each section of the split stream and having a substantially horizontal lower edge, means to turn the gas streams sharply beneath said lower edge, said splitting means comprising a flue for merging and carrying off said streams, a fly-ash receptacle beneath said bafile edge, and a fly-ash wash pipe adjacent the high edge of said deflector wall and having nozzles directed away from the combustion chamber. 7

6. In a domestic fluid heater, in combination, water cooled walls forming a closed compartment, a wall extending transversely of said compartment for a part of the height thereof to divide it into a combustion chamber and space: for passages with convection-heated surfaces, a deflector wall on top of said transverse wall extending over the chamber and oppositely beyond said transverse wall and inclined away from said combustion chamber, means in the vertical passage behind said transverse wall and below the deflector wall to split the gas stream and reduce its total crosssection and increase its velocity, a bailie for each section of the split stream and having a substantially horizontal lower edge, means to turn the gas streams sharply beneath said lower edge, said splitting means comprising a flue for merging and carrying oif said streams, a fly-ash receptacle beneath said bafiie edge, a fly-ash wash pipe adjacent the high edge of said deflector wall and having nozzles directed away from the combustion chamber, and a second wash pipe adapted to spray the baffle and adjacent areas, the drainage from both pipes being received into said receptacle. V

'7. In a domestic fluid heater, in combination, water cooled walls forming a closed compartment, a water cooled wall extending transversely of said compartment for a portion of the height thereof to divide it into a combustion chamber and a space'having vertical passages with convection-heated surfaces, a deflector wall on top of said transverse wall and inclined downwardly away from the combustion chamber toward a portion of the passages, a fly-ash receptacle at the bottom of said portion and water spray means to clean all of the said passage walls, said deflector inclination directing, water into said receptacle and away from the combustion chamber.

8. In a domestic fluid heater, in combination, water cooled-walls forming a closed compartment,

a wall transverse to said compartment dividing the lower part thereof into a combustion chamber and a space having passages with convectionheated surfaces, an inclined deflector wall on top of said transverse wall sloping away from the combustion chamber, a steeply inclined bafile extending from the lower edge of said deflector wall into the said space behind the transverse wall, a flue extending horizontally through said battle and having a gas entrance in front of said bafile, and a fly-ash receptacle beneath the lower edge of said bafile and flue.

9. In a domestic fluid heater, in combination, water cooled walls forming a closed compartment, a wall transverse to said compartment dividing the lower part thereof intoa combustion chamber and a space having vertical passages with convection-heated surfaces, an inclined deflector wall on top of said transverse wall sloping away from the combustion chamber, a steeply inclined baflle extending from the lower edge of said deflector wall into the said space behind the transverse wall, a flue extending horizontally through said baflie and having a gas entrance in front of said bafile, and installed means to spray water for cleaning fly-ash from substantially all passage walls, said inclined deflector wall directing the used water and ash toward said space.

10. In a domestic fluid heater, in combination, water cooled Walls forming a closed compartment, a wall transverse to said compartment dividing the lower part thereof into a combustion chamber and a space having vertical passages with convection-heated surfaces, an inclined deflector wall on top of said transverse wall sloping away from the combustion chamber, a steeply inclined baffle extending from the lower edge of said deflector wall into the said space behind the transverse wall, a flue extending horizontally through said baflle and having a gas entrance in front of said bafile, a fly-ash receptacle beneath the lower edge of said baflle and flue, and means to spray Water for cleaning fiy-ash from substantially all passage walls, said deflector wall diverting used water and ash toward said receptacle.

11. In a fluid heater of the type described, in combination, a combustion chamber, means forming water-cooled radiant heat absorbing surfaces immediately about the combustion chamber and more remote, water-cooled, convection-heated o surfaces enclosing gas passages, means for burning a fly-ash forming fuel in the combustion chamber, and passing the products of combustion through said gas passages, perforated water spray pipes built permanently into said gas passages so as to be completely surrounded by convectionheated surfaces, the spray from the said pipes being directed to wash fly-ash from all of the surrounding convection-heated surfaces, the lower of such surfaces being inclined away from the combustion chamber and the sprays so directed that water may be sprayed over substantially all of the convection-heated surfaces to clean them while the fuel is burning without quenching its fire.

12. In a domestic fluid heater, in combination, water cooled walls forming a closed compartment, a wall extending transversely of said compartment for a part of the height thereof to divide it into a combustion chamber and space for passages with convection-heated surfaces, a deflector wall on top of said transverse wall and inclined away from said combustion chamber, a substantially horizontal flue open at the front in the space behind said transverse wall and below the deflector wall to split the downcoming gases into two streams of reduced total cross-section, a baille for each section of the stream and having a substantially horizontal lower edge, means to turn the gas streams beneath said baffies and merge and direct them into said flue, a fly-ash receptacle beneath the baffle edges and fly-ash wash means adjacent the high edge of said deflector wall. 1

13. In a domestic fluid heater in combination, a combustion chamber, a plurality of connected gas passages defined by convection-heated walls, a flue, said walls being so disposed that the gas passages extend from the combustion chamber to "said flue in the form of a cyclonic dust collector wherein the dust is deposited on the outer walls of the passages, means for burning a fly-ash forming fuel under forced draft in said combustion chamber and water spray means mounted adjacent the inner walls. of said passages and having nozzles directed toward the outer walls thereof to wash away the fly-ash, a fly-ash receptacle, said inner walls being so disposed as to drain all water away from the combustion chamber and toward said receptacle.

DONALD J. MOSSHART. 

